EP93XX / EDB9315A Audio Issues

[cubicool@gmail.com (Jeremy Moles)]

On 09/10/2014 01:57 PM, Jeremy Moles wrote:
> (I'm cross-posting this to the linux-arm-kernel and alsa-devel lists, 
> as recommended):
>
> I'm looking for anyone who has successfully used the EP93XX/EDB9315A 
> demo board's sound infrastructure. I have been working with Hartley 
> Sweeten on patching some DMA coherency mask issues (successfully), and 
> while this makes the kernel stop complaining (and allows the userspace 
> to "appear" to work) I never actually get any sound out of the machine 
> on newer kernels.
>
> I do, however, have an existing (binary-only) 2.6.21 kernel from the 
> client where sound _IS_ functional; thus, I know the system can 
> POTENTIALLY work, and that the problem is software-based.
>
> At this point, I have a mountain of information I can provide about 
> the state of my EDB9315A board, but what I'm really looking for is 
> someone to connect with and/or have consult with us to get sound 
> working on newer kernels with this board exactly (although other 
> EP93XX boards might be similar, I'm so mistrustful of everything at 
> this point I'm looking for someone else with this hardware EXACTLY).
>
> I've tried 3.15-3.17, all with the same results. aplay/alsamixer see 
> the device, appear to interact with it in a normal fashion (it even 
> mutes/unmutes the device every time you touch it), but no sound is 
> ever produced. It is possible, of course, the problem is in userspace 
> (I'm using a custom Yocto-based image), but I'm doubtful of that.
>
> At any rate, any help would be greatly appreciate, although i realize 
> this is fringe hardware. :)

I'd like to try and give this thread a bump; perhaps I'll get lucky and 
find what I'm fishing for. :)

I've e-mailed the EDB9315A's listed maintainer, but he no longer works 
with the hardware. Hartley Sweeten (the maintainer of the more general 
EP93XX) has been helping me a great deal, but I'm looking for someone 
else with physical access to his hardware. Some people have commented 
that the hardware is old and difficult to acquire, but our client 
literally has thousands of these boards running 2.6 (and wants to 
upgrade to 3.15+, which currently doesn't support sound--though supports 
everything else).